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Hi! I just purchased a 1944 Cape and I need to replace the existing electric hot water heater. I have done some research and determined that I would like to buy a 40 gallon tank with a good warranty. Any suggestions on an efficient, affordable unit? If it makes any difference, I have a boiler that uses oil right now, but I will eventually be replacing it with a gas boiler. The city gas line is available to me, although it is not currently in my home so a gas water heater is not an option at the moment. Thanks!

You can get 6,10 and 12 year warranted water heaters. In most cases they are the same tank. The additional cost is like buying a extended warranty. What it gives you is a replacement tank if it fails within the warranty period it will not cover your installation cost.

For anyone like yourself that already has a boiler, either oil-fired or gas fired, it is strongly suggested that you consider having what's called an indirect hot water heater installed now with your present boiler, or when you buy a new gas-fired boiler.

Indirect hot water heaters (IHWH) are known as heat exchanger companions of hot water heat boilers, and are considered by many as the best, and most efficient way of obtaining hot tap water, or domestic hot water (DHW); since you already have a boiler, you have ready hot water that can be pumped thru a tank within a tank (IHWH) to heat the DHW, usually a 40 gallon size capacity; there is no need to have a separate gas burner for the IHWH, and no need to have a flue connection to the chimney, etc.

Upfront costs for the IHWH are higher than buying a gas water heater, but the IHWH will last for decades without problems, especially if you have reasonably soft water at your location.

Typical installation costs with the unit are approx $2k; you'll never run out of hot water once you have this type of unit installed.

The sites below explain the benefits and drawbacks of the various DHW heating tanks; indirect units by Triangle Tube, HTP Superstor, Weil-Mclain, Lochinvar and TFI Everhot, among others are recommended.

I would forget about an additional oil fired or electric water heater. Brewster is 100% correct. If a boiler is present, certainly install an indirect fired water heater. But there is one catch. That doesn't work with steam systems. If you have a steam system, then the indirect fired water heater can't be put in the loop. They have yet to invent an indirect tank that uses steam. But if your systems Hydronic, then your all set.

I would forget about an additional oil fired or electric water heater. Brewster is 100% correct. If a boiler is present, certainly install an indirect fired water heater. But there is one catch. That doesn't work with steam systems. If you have a steam system, then the indirect fired water heater can't be put in the loop. They have yet to invent an indirect tank that uses steam. But if your systems Hydronic, then your all set.

You can use a indirect on steam. You just use the trappings on the boiler that are inside the water level of the boiler.

the indirect or direct our a little more expensive but our nice as far as John stated the 6, 10 , 12 year warranty is the same tank but there is a difference the 6 year has one anode rod and the 10+ has 2 the average life span of an anode rod is between 4-6 years of age completely depleted is 6 you hear of the water heater's that die 6 years and 3 months later well that's why the anode rod depleted. According to the manufactures of water heater's a tank only has 30 days of life without an anode rod so if your anode rod is depleted it has 30 days or less till it leaks I have yet to change out a water heater that leaked from tank with a good anode rod so that being said save the extra cost of unit and change the anode rod every 4-5 years at least have it inspected.